Heating device

Abstract

To provide a heating device which can meet an instantaneous heater output requirement.SOLUTION: A heating device 10 has an electric resistance element 11 which can be heated according to a plurality of power consumption requirements from a vehicle, an upper layer switching element 121 and a lower layer switching element 122 which are connected in series through the electric resistance element 11, a boot strap capacitor 125 which accumulates electric charges so that the upper layer switching element 121 is made in an open state, and control means 13 which controls opening / closing the upper layer switching element 121 and the lower layer switching element 122, and thereby conducts / interrupts the electric resistance element 11, wherein when determining that there is no power consumption requirement, the control means 13 closes the upper layer switching element 121, opens the lower layer switching element 122, and accumulates the electric charges in the boot strap capacitor 125.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a heating device for a vehicle. [Background technology]

[0002] Conventionally, air conditioning systems for vehicles, regardless of whether they are engine vehicles, electric vehicles, hybrid vehicles, etc., are equipped with a heating device (heat medium heating device) that heats a heat medium circulating through an air conditioning heat exchanger (heater core) (see, for example, Patent Document 1).

[0003] Also known is a vehicle air conditioning system, particularly for electric vehicles and hybrid vehicles, in which a heater in a heating device is used for both air conditioning purposes, where it functions as a heater in an air conditioner, and for regeneration purposes, where it functions as a load that consumes regenerative power generated by regeneration (see, for example, Patent Document 2). Specifically, in the vehicle air conditioning system described in Patent Document 2, a high-voltage auxiliary device (heating device) having a high-voltage heater is connected to an air conditioning control unit (air conditioning ECU) and a vehicle control unit (vehicle ECU), which are external devices, via communication lines. The high-voltage auxiliary device has an arbitration unit that arbitrates the acquired requests when it receives multiple different requests from the external devices. When the arbitration unit receives an air conditioning request from the air conditioning ECU to operate the high-voltage heater for air conditioning purposes and a regeneration request from the vehicle ECU to operate the high-voltage heater for regeneration purposes, it arbitrates the acquired requests by summing the instruction values ​​included in the two requests or by assigning priorities to the two requests. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2021-54145 [Patent Document 2] Japanese Patent Application Laid-Open No. 2018-114943 Summary of the Invention [Problem to be solved by the invention]

[0005] However, conventional heating devices have had the problem that they are not adequately equipped to deal with situations where heater output is required instantaneously.

[0006] Specifically, for example, in a vehicle equipped with a regenerative device and a power storage device, when the regenerative power generated by the regenerative device exceeds the amount of power stored in the power storage device, it is desirable that the surplus power be consumed as heater output as early (instantaneously).The heater output is ultimately controlled by the switching element that energizes the heater, and even if priority is given to the heater output request (the regenerative request in the case of Patent Document 2), if the start of voltage control by the switching element is slow, there is a problem that the instantaneous output request cannot be met.

[0007] SUMMARY OF THE INVENTION In view of the above circumstances, the present invention aims to provide a heating device that can meet the demand for instantaneous heater output. [Means for solving the problem]

[0008] The present invention relates to a power supply circuit for a vehicle, the power supply circuit comprising: an electric resistance element capable of generating heat in response to a plurality of power consumption requests from a vehicle; an upper layer switching element and a lower layer switching element connected in series via the electric resistance element; a bootstrap capacitor for storing charge for turning the upper layer switching element into an open state; and control means for controlling the opening and closing of the upper layer switching element and the lower layer switching element to perform conduction / cutoff control of the electric resistance element; At least one of the plurality of power consumption requests is a request transmitted based on control of a regenerative device and / or a power storage device of the vehicle, and is a power consumption request (hereinafter referred to as an "excess power consumption request") for consuming surplus power when regenerative power generated by the regenerative device during braking exceeds the amount of power stored in the power storage device, The aforementioned the control means has a high-speed start processing unit that controls the opening and closing of the upper layer switching elements and the lower layer switching elements so that an average increase rate of power consumption of the electric resistance elements increases when the current supply to the electric resistance elements is increased; when it is determined that none of the plurality of power consumption requests exists, the control means closes the upper layer switching element and opens the lower layer switching element to store the charge in the bootstrap capacitor; When it is determined that there is a request to consume excess power, the electrical resistance element is energized to generate heat, and when at least the request to consume excess power is accepted, control is performed by the fast start processing unit, and the control means sufficiently charges the bootstrap capacitor while waiting for acceptance of the power consumption request, so that when the control means determines that there is a request to consume power, control by the fast start processing unit is immediately started. The present invention relates to a heating device characterized by the above. [Effects of the Invention]

[0009] The heating device of the present invention has the excellent effect of being able to provide a heating device that can respond to instantaneous heater output demands. [Brief explanation of the drawings]

[0010] [Figure 1] 1A and 1B are diagrams showing the configuration of a heating device of the present invention, in which (A) is a schematic block diagram, (B) is a plan view showing the outline of the configuration of the device, and (C) is a side view showing the outline of the configuration of the device. [Figure 2] FIG. 2 is a circuit diagram showing a control unit and a driving unit in the heating device of the present invention. [Figure 3] FIG. 1 is a functional block diagram illustrating a heating device according to the present invention. [Figure 4] 1 is a diagram for explaining voltage control in the heating device of the present invention, in which (A) to (D) are diagrams showing the change in duty ratio as the program processing cycle of the slow start processing unit passes through in this order, (E) is a diagram showing an example of the change over time in the output (power) of the electrical resistance element by the slow start processing unit, (F) and (G) are diagrams showing the change in duty ratio as the program processing cycle of the fast start processing unit passes through in this order, (H) is a diagram showing an example of the change over time in the output (power) of the electrical resistance element by the fast start processing unit, and (I) to (J) are diagrams showing an example of the change over time in the output (power) of the electrical resistance element when the slow start processing unit and the fast start processing unit are superimposed. [Figure 5] 1A and 1B are diagrams for explaining a pre-charging means, in which FIG. 1A shows voltage control and the charge accumulation state of a bootstrap capacitor when pre-charging is performed, and FIG. 1B shows voltage control and the charge accumulation state of a bootstrap capacitor when pre-charging is not performed. [Figure 6] FIG. 4 is a flowchart showing the flow of a heater control process in the heating device of the present invention. [Figure 7] 4 is a timing chart showing command signals included in a power consumption request in the heating device of the present invention and changes in the state of the heating device based on the command signals. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. Figures 1 to 7 show an example of an embodiment of the present invention, and in the figures, parts with the same reference numerals represent the same configuration. In addition, some components are omitted as appropriate in each figure to simplify the drawings. In addition, the shapes and dimensions of some components are exaggerated as appropriate in each figure.

[0012] <Overall configuration of the heating device> FIG. 1 is a diagram illustrating the heating device 10 of this embodiment, where FIG. 1(A) is a block diagram showing an overview of the heating device 10, FIG. 1(B) is a plan view showing an outline of the configuration of the heating device 10, and FIG. 1(C) is a side view showing an outline of the configuration of the heating device 10.

[0013] As shown in FIG. 1(A), a heating device 10 of this embodiment constitutes a part of a vehicle air conditioning system S. The heating device 10 is a heat medium heating device that heats a heat medium Hm circulating via an air conditioning heat exchanger (heater core) in a vehicle air conditioning system 21. A vehicle in which the heating device 10 of this embodiment is installed is, for example, an electric vehicle or a hybrid vehicle, and has a regenerative device 4, and is configured so that regenerative power generated by the regenerative device 4 during braking is stored in a power storage device 6. The power storage device 6 serves as a DC power source for supplying power to the heating device 10.

[0014] In this vehicle air conditioning system, the heating device 10 is used for consuming power to heat the air inside the vehicle in the vehicle air conditioner 21 (air conditioning use), and for consuming surplus power when the regenerated power exceeds the amount of power stored in the power storage device 6 (surplus power consumption use).

[0015] In other words, the heating device 10 receives a power consumption request (first power consumption request, hereinafter also referred to as the "air conditioning power consumption request") for heating air in the vehicle air conditioning device 21, which is transmitted based on the control of the vehicle air conditioning device 21, and a power consumption request (second power consumption request, hereinafter also referred to as the "surplus power consumption request") for consuming surplus power when the regenerative power generated by the regenerative device 4 during braking exceeds the amount of power stored in the power storage device 6, which is transmitted based on the control of the vehicle's regenerative device 4 and / or the power storage device 6, and heats the heat medium Hm based on these requests.

[0016] The first power consumption request is a request signal that includes at least information (first request value) corresponding to the amount of power to be consumed for air conditioning purposes, and the second power consumption request is a request signal that includes at least information (second request value) corresponding to the amount of power to be consumed for surplus power consumption purposes.

[0017] In the example shown in FIG. 1(A), the sender of the first power consumption request (first request sending means) is the control unit (ECU: Electronic Control Unit) of the vehicle air conditioning device 21, and the sender of the second power consumption request (second request sending means) is, for example, the control unit (ECU) of the charging control device 22 that monitors and controls the regeneration device 4 and / or the power storage device 6, and these and the heating device 10 are connected by a wired or wireless communication line.

[0018] Detailed illustrations of the ECU of the air conditioner 21 (hereinafter referred to as air conditioner ECU 1) and the ECU of the charging control device 22 (hereinafter referred to as charging ECU 2) are omitted, but each includes a CPU (Central Processing Unit), memory such as ROM (Read Only Memory) or RAM (Random Access Memory), a non-volatile storage unit such as an HDD (Hard Disk Drive) or SSD (Solid State Drive), and a communication control unit. The CPU, memory, storage unit, and communication control unit are connected to each other via an internal bus so that they can communicate with each other. The communication control unit is connected to the heating device 10 via a communication line and is capable of transmitting information (signals) such as power consumption requests to the heating device 10.

[0019] 1(A) to 1(C), the heating device 10 includes, for example, an electric resistance element 11 (11A, 11B), a driving means 12 for the electric resistance element 11, a control means (controller) 13, a request acquisition means 14, and various sensors (not shown). The electric resistance element 11 generates heat when energized in response to a plurality of power consumption requests transmitted from a computer mounted on the vehicle, and constitutes a heater of the heating device 10. In the following description and drawings, the term "heater" may be used, but this refers to the electric resistance element 11.

[0020] The driving means 12 (heater driving means 12) for the electric resistance element 11, the control means 13, and the request acquisition means 14 are arranged on the control board 1 as electronic components. The control means 13 is composed of a calculation device (e.g., a CPU), storage means (volatile memory (RAM, ROM) and non-volatile storage means (HDD, SDD)), etc. The control means 13 stores various programs in the storage means and executes the programs or various calculations to comprehensively control each part (each component) of the heating device 10. The control means 13 may be an ECU of the heating device 10.

[0021] In this example, the request acquisition means 14 includes a communication means 19 that communicates with the air conditioning ECU 1 and the charging ECU 2, and is a means for receiving the first power consumption request, the second power consumption request, and various other requests from the air conditioning ECU 1 and the charging ECU 2.

[0022] 1B and 1C, the heater driving means 12 includes switching elements 121 and 122 and their drivers (not shown in FIG. 1), etc. The control means 13 controls the opening and closing of the switching elements 121 and 122, thereby controlling the conduction and cutoff of the electrical resistance element 11.

[0023] The electric resistance element 11 and the control board 1 are housed in a case 2, which is provided with a pipe 3 that connects the inside of the case 2 with the outside. Two pipes 3 are provided to form an inlet 3A and an outlet 3B, and the inside of each pipe serves as a flow path for the heat medium Hm. The heat medium Hm is, for example, water, but it may also be coolant or oil. As shown in FIG. 1(C), the case 2 is made up of an upper case 2A and a lower case 2B, each having a heater accommodating recess 21, and the electric resistance element 11 is housed in the heater accommodating space 22 formed by joining these together.

[0024] The power supply unit 5 has a power supply terminal 5A, and the power supply terminal 5A is connected to the control board 1 by a wire (not shown). Power is supplied to the power supply unit 5 from the power storage device 6. The voltage applied to the power supply unit 5 is, for example, 120V to 420V.

[0025] With this configuration, the heating device 10 supplies power from the power storage device 6 to the electrical resistance element 11 to generate heat based on the first power consumption request from the air conditioning ECU 1 and / or the second power consumption request from the charging ECU 2. This consumes power equivalent to the amount of heat generated.

[0026] FIG. 2 is a circuit block diagram showing an example of the heater driving means 12 and the control means 13 of the heating device 10. As shown in FIG.

[0027] The heater driving means (heater driving circuit) 12 includes, for example, an upper layer switching element 121, a lower layer switching element 122, an upper layer driver 123, a lower layer driver 124, an upper layer capacitor 125, a lower layer capacitor 126, and the like.

[0028] The upper layer switching element 121 and the lower layer switching element 122 are, for example, voltage-driven transistors. More specifically, they are insulated gate field effect transistors in which an n-channel is formed by applying a positive gate voltage to a terminal on the low potential side, and specifically, for example, insulated gate bipolar transistors (IGBTs).

[0029] Hereinafter, for convenience of explanation, the upper layer switching element 121 will be referred to as the upper layer IGBT 121, and the lower layer switching element 122 will be referred to as the lower layer IGBT 122. The upper layer IGBT 121 and the lower layer IGBT 122 are connected in series via the electrical resistance element 11. The high potential side terminal (collector) of the upper layer IGBT 121 is connected to the positive electrode of the high voltage power supply 131, and the low potential side terminal (emitter) is connected to the high potential side terminal of the electrical resistance element 11. Furthermore, the low potential side terminal of the electrical resistance element 11 is connected to the high potential side terminal (collector) of the lower layer IGBT 122, and the low potential side terminal (emitter) of the lower layer IGBT 122 is connected to the negative electrode of the high voltage power supply 131.

[0030] The upper layer driver 123 is a circuit that applies a gate-emitter voltage to the gate terminal of the upper layer IGBT 121 based on a driver drive signal input from the control means 13. The lower layer driver 124 is a circuit that applies a gate-emitter voltage to the gate terminal of the lower layer IGBT 122 based on a driver drive signal input from the control means 13.

[0031] The power supply input terminal of the upper layer driver 123 is connected to the driver power supply 130 via an upper layer capacitor 125. This upper layer capacitor 125 is a bootstrap capacitor that stores charge to turn the upper layer IGBT 121 into an open state (on state). The power supply input terminal of the lower layer driver 124 is connected to the driver power supply 130 via a lower layer capacitor 126.

[0032] The control means 13 controls the opening (on) / closing (off) of the upper layer IGBT 121 and the lower layer IGBT 122, thereby controlling the conduction / cutoff of the electrical resistance element 11. Specifically, the control means 13 supplies driver drive signals of pulse waveforms with different timings to the driver drive signal input terminals of the upper layer driver 123 and the lower layer driver 124. In synchronization with the driver drive signal, the upper layer driver 123 outputs a voltage of pulse waveform equivalent to the voltage obtained by adding the gate-emitter voltage of the upper layer IGBT 121 itself to the voltage of the high-voltage power supply 131 to the gate of the upper layer IGBT 121. In synchronization with the driver drive signal supplied from the control means 13, the lower layer driver 124 outputs a voltage of pulse waveform equivalent to the voltage of the driver power supply 130 to the gate of the lower layer IGBT 122.

[0033] As a result, the channels of the upper layer IGBT 121 and the lower layer IGBT 122 are opened (on) and closed (off) at predetermined timings. During the period when the upper layer IGBT 121 and the lower layer IGBT 122 are on, the electrical resistance element 11 is energized, and heat is generated, consuming power equivalent to the amount of heat generated.

[0034] The heater driving means 12 may be any circuit that drives (turns on or off) the electrical resistance element 11 by turning on / off the upper layer IGBT 121 and the lower layer IGBT 122, and in addition to the configuration shown in Figure 2, the heating device 10 of this embodiment has a known configuration (e.g., a diode) as a circuit that normally drives the electrical resistance element 11, upper layer IGBT 121, and lower layer IGBT 122.

[0035] <Heating device function> 3 is a block diagram illustrating the function of the heating device 10 of this embodiment. As already described, the heating device 10 receives at least an air conditioning power consumption request (first power consumption request) and a surplus power consumption request (second power consumption request), and based on these requests, energizes the electric resistance element 11 to heat the heat medium Hm.

[0036] Here, particularly when a request to consume surplus power is received, it is desirable to promptly consume the requested value (second requested value) of power because the regenerative power exceeds the amount of power stored in the power storage device 6. Therefore, the heating device 10 of this embodiment has multiple functions for promptly consuming the requested power. Specifically, these multiple functions are a forced shutoff function, a request acquisition function, a request determination function, a start processing determination function, a power control function, and a pre-charge function, and these functions are realized by the actual means of the heating device 10 shown in FIGS. 1 and 2 (hardware such as electronic components (circuits and elements) provided on the control board 1) and the execution of software (programs) stored in the control means 13.

[0037] 3 is a block diagram illustrating the heating device 10 from the viewpoint of means for realizing the above functions, and the heating device 10 has, for example, forced shutoff means 20, request acquisition means 14, request determination means 15, start processing determination means 16, power control means 17, and pre-charging means 18. These are realized by various electronic components arranged on, for example, one or more control boards 1, and are comprehensively controlled by control means 13. In other words, some or all of these means also include the control means 13.

[0038] << Forced shutoff method >> The forced shutdown means 20 realizes the forced shutdown function and forcibly prohibits power consumption by the electric resistance element 11 based on (determines) a predetermined condition (forced shutdown condition) if the condition is met. The forced shutdown condition is met, for example, when an abnormality occurs in the heating device 10. Specifically, for example, (1) a protection / fault sensor is detected, or (2) failure detection by the overvoltage sensor is not completed. The heating means 10 has a protection / fault sensor (not shown) that detects a failure in the control board 1 when the temperature of the control board 1 exceeds the allowable temperature of the electric resistance element 11, the upper layer IGBT 121, and the lower layer IGBT 122. "Detection of the protection / fault sensor" refers to a state in which the electric resistance element 11 cannot be safely operated. If at least one of (1) and (2) above is met, the forced shutdown means 20 determines that the forced shutdown condition is met and forcibly prohibits power consumption (heater heating) by the electric resistance element 11, regardless of whether a power consumption request is made.

[0039] <<Request acquisition means>> The request acquisition means 14 realizes a request acquisition function and, in this example, includes a communication means 19 that communicates with the air conditioning ECU 1 and the charging ECU 2, and is a receiving means that receives various requests, including a first power consumption request from the air conditioning ECU 1 and a second power consumption request from the charging ECU 2. The request acquisition means 14 can acquire multiple power consumption requests (here, the first power consumption request from the air conditioning ECU 1 and the second power consumption request from the charging ECU 2) almost simultaneously. More specifically, for example, the control means 13 executes interrupt processing (hardware interrupt and / or software interrupt, or external interrupt and / or timer interrupt) for each program processing cycle (hereinafter referred to as the program processing cycle), causing the request acquisition means 14 to acquire multiple power consumption requests. Note that the interrupt by the request acquisition means 14 is not limited to being executed for each program processing cycle, but can also be executed over multiple program processing cycles, which can be defined as an "interrupt cycle." That is, the multiple power consumption requests are acquired in synchronization with the interrupt period, that is, both requests are acquired synchronously (almost simultaneously).

[0040] The first power consumption request and the second power consumption request are control commands for the heating device 10, and in principle, are constantly acquired while the heating device 10 is operating. In other words, even when there is no actual request for each power consumption, a request (command) that "there is no requested value" is acquired. Here, "there is no requested value" means, for example, that the requested value is "less than the minimum requested threshold," and the minimum requested threshold is, for example, 200 W. Note that the requested value is information indicating (corresponding to) the actual heat generation (power consumption) of the electrical resistance element 11, but in this embodiment, for convenience of explanation, it will be described as being the same numerical value as the heat generation amount.

[0041] The request acquisition means 14 enables the heating device 10 to acquire the first power consumption request and the second power consumption request almost simultaneously and periodically without any difference due to delay or priority, even if the sender of the first power consumption request (first request transmission means, here the air conditioning ECU 1) and the sender of the second power consumption request (second request transmission means, here the charging ECU 2) are separate means.

[0042] <<Request determination means>> The request determination means 15 realizes a request determination function and determines whether or not a power consumption request actually exists based on the multiple power consumption requests acquired by the request acquisition means 14. Specifically, the request values ​​included in the multiple power consumption requests are compared and the largest request value is determined. In this example, the first request value included in the first power consumption request and the second request value included in the second power consumption request are compared, the larger request value is determined, and the request value is set as the target value for actual power consumption (target power consumption G).

[0043] In addition, if there is no actual power consumption request (if the request value is less than the minimum request threshold), for example, if a first power consumption request is acquired with the first request value set to "0 (W)" and a second power consumption request is acquired with the second request value set to "10 (W)", both are less than the minimum request threshold, so it is determined that there is no power consumption request.

[0044] Here, even if each of the acquired multiple power consumption requests "contains a power consumption request," if the above-mentioned forced shutdown condition is met, the forced shutdown means 20 forcibly prohibits power consumption.

[0045] In other words, in this embodiment, "heater off," i.e., a state in which no current is flowing through the electrical resistance element 11, can occur when the heater is off because the "required value is less than the minimum required threshold value," or when the heater is off because the forced shut-off condition is met.

[0046] In this way, in this embodiment, the request determination means 15 determines the maximum request value among multiple power consumption requests as the target power consumption G, so that when multiple power consumption requests are acquired almost simultaneously, it is possible to avoid a shortage of the request value (target power consumption G) due to, for example, a larger request value being overwritten by a smaller request value.

[0047] <<Start processing determination means>> The start processing determination means 16 realizes the start processing determination function, and is a means for determining and deciding the speed (degree) of increasing the current supply to the electrical resistance element 11 (starting from a cut-off state (increasing from a non-current-supply state)) in accordance with the acquired power consumption request.

[0048] The power control means 17 (control means 13) has a fast start processing unit 171 and a slow start processing unit 172. The fast start processing unit 171 is a unit that controls the switching of the upper layer IGBT 121 and the lower layer IGBT so that the target power consumption G (determined required value) is reached in a short time when the current supply to the electrical resistance element 11 is increased. The slow start processing unit 172 is a unit that controls the switching of the upper layer IGBT 121 and the lower layer IGBT 122 so that the target power consumption G (determined required value) is reached in a longer time than the fast start processing unit 171 when the current supply to the electrical resistance element 11 is increased.

[0049] The start processing determination means 16 determines, based on predetermined determination conditions, whether the acquired power consumption request should be processed by the fast start processing unit 171 or the slow start processing unit 172. As an example of the predetermined determination conditions, if the power consumption request accepted by the request determination means 15 is a first power consumption request (air conditioning power consumption request), processing is performed by the slow start processing unit 172, and if it is a second power consumption request (surplus power consumption request), processing is performed by the fast start processing unit 171.

[0050] <<Power control means>> The power control means 17 realizes a power control function, controls the voltage applied to the upper layer IGBT 121 and the lower layer IGBT 122, and controls conduction to the electrical resistance element 11. The power control means 17 controls the voltage, for example, by a PWM (Pulse Width Modulation) method. That is, the power control means 17 controls the voltage applied to the gates of the upper layer IGBT 121 and the lower layer IGBT 122 by PWM control according to the required power, and controls the opening and closing of the upper layer IGBT 121 and the lower layer IGBT 122.

[0051] The power control means 17 also includes, for example, a high-speed start processing unit 171 and a low-speed start processing unit 172. Based on the determination result of the start processing determination means 16, the power control means 17 allocates the received power consumption request to the high-speed start processing unit 171 or the low-speed start processing unit 172.

[0052] When increasing the current supply (power consumption) to the electrical resistance element 11, the fast start processing unit 171 sets PWM control parameters so that the target power consumption G is reached in a short time from the start of the increase (start of PWM control) or so that the rate of increase in power consumption is high, and controls the switching of the upper layer IGBT 121 and the lower layer IGBT 122. When increasing the current supply to the electrical resistance element 11, the slow start processing unit 172 sets PWM control parameters so that the target power consumption G is reached in a long time from the start of the increase compared to the fast start processing unit 171, or so that the rate of increase in power consumption is slower than that of the fast start processing unit 171, and controls the switching of the upper layer IGBT 121 and the lower layer IGBT 122.

[0053] 4A to 4D are conceptual diagrams showing the change over time of the control by the fast start processing unit 171 and the control by the slow start processing unit 172 for a predetermined number of program processing cycles (hereinafter referred to as a "processing cycle group"), where one program processing cycle is defined as a program processing in which a single power consumption request is acquired (accepted) and PWM control is performed based on that request. Each of FIGS. 4A to 4D is a conceptual diagram showing the change over time from FIG. 4A to FIG. 4D for every 800 program processing cycles (800 processing cycle group), i.e., a total of 2,400 program processing cycles from FIG. 4A to FIG. 4D. These diagrams show an example of PWM control in the slow start processing unit 172, as well as the change over time of the duty ratio. FIG. 4E is a diagram showing an example of the change over time of the output (power) of the electrical resistance element 11 from FIG. 4A to FIG. 4D, where the horizontal axis represents time T and the vertical axis represents output voltage W. 4(F) and 4(G) are conceptual diagrams showing the change from 4(F) to 4(G) in a program processing cycle group (e.g., every 800 processing cycle groups), i.e., the transition over time for a total of 800 program processing cycles. These diagrams are an example of PWM control in the fast start processing unit 171, showing the change in duty ratio over time. FIG. 4(H) is a diagram showing an example of the change in output (power) over time in the electrical resistance element 11 from 4(F) to 4(G), with the horizontal axis representing time T and the vertical axis representing output voltage W. Also, "G'" in 4(D) and 4(G) represents the overlap amount between the upper layer IGBT 121 and the lower layer IGBT 122, and the sum of their areas is the set target power consumption G (required value). The sum of the areas of the overlap amount G' in 4(D) is the height shown in 4(E) and the target power consumption G. Similarly, the total area of ​​the overlap amount G' in FIG. 1(G) is the height shown in FIG. 1(H), which is the target power consumption G. In FIG.

[0054] As shown in the figures (A) to (D), the power control means 17 of this embodiment controls the voltage applied to each gate of the upper layer IGBT 121 and the lower layer IGBT 122, for example by PWM control, and changes the open (on) / closed (off) ratio (duty ratio) of each over time to control the conduction state (amount of current flowing) to the electrical resistance element 11. When the amount of current flowing to the electrical resistance element 11 changes, the amount of heat generated by the electrical resistance element 11 changes, and the amount of power consumed changes.

[0055] The slow start processing unit 172 sets the increase (rising amount) of the duty ratio per one program processing cycle (e.g., 1.0 msec), i.e., the average increase rate of the duty ratio when considered on the time axis, to be smaller than that of the fast start processing unit 171, which will be described later. As a result, as shown in FIGS. 10A to 10D, the slow start processing unit 172 PWM-controls the upper layer IGBT 121 and the lower layer IGBT so that the duty ratio increases more gradually than that of the fast start processing unit 171, thereby controlling the conduction of the electrical resistance element 11. As a result, the average increase rate of the power consumption of the electrical resistance element 11 becomes slower (becomes slower), and the time from the start of the increase in power consumption (start of PWM control) to the arrival at the target duty ratio Dm corresponding to the requested value of the received power consumption request (overlap amount G', target power consumption G) becomes longer, specifically, more than one second (in the above example, 2400 times × 1.0 sec = 2.4 sec). Hereinafter, the control by the slow start processing unit 172 is referred to as "slow start processing." In this case, as shown in the same figure (E), the output (power consumption) of the electrical resistance element 11 rises from the start SS of the slow start processing (after the PWM control start signal turns on ("H")) while inclining at a certain angle (this angle means the average rate of increase in power consumption) according to the change (amount of increase) in the duty ratio, and reaches the target power consumption G.

[0056] In contrast, the fast start processing unit 171 sets the increase (rising amount) of the duty ratio per one program processing cycle (for example, 1.0 msec), i.e., the average increase speed of the duty ratio when considered on the time axis, to be larger than that of the slow start processing unit 172. As a result, as shown in (F) and (G) of the same figure, the fast start processing unit 171 PWM controls the upper layer IGBT 121 and the lower layer IGBT so that the duty ratio increases more than that of the slow start processing unit 172, and controls the conduction to the electrical resistance element 11. As a result, the average rate of increase in power consumption of the electrical resistance element 11 increases (becomes faster). Assuming that the target duty ratio Dm corresponding to the requested value (overlap amount G' and set target power consumption G) included in the received power consumption request is the same as the target duty ratio Dm set by the slow start processing unit 172, the time required to reach this value is shorter than in the slow start processing, specifically, less than 1 second (in the above example, 800 times × 1.0 sec = 0.8 sec). Hereinafter, this control by the fast start processing unit 171 will be referred to as the "fast start processing." In this case, as shown in FIG. 1H, the output of the electrical resistance element 11 increases at a steeper angle (this angle indicates the average rate of increase in power consumption) than the slow start processing unit 172, depending on the amount of change (increase) in the duty ratio, from the start point FS of the fast start processing (after the PWM control start signal turns on ("H")), and reaches the target power consumption G.

[0057] In the power control means 17, for example, when the electrical resistance element 11 is not energized (a "no power consumption request" state) and a new second power consumption request (surplus power consumption request) is received (when the energization (power consumption amount) to the electrical resistance element 11 is to be increased (started), the high-speed start processing unit 171 controls so that the average rate of increase in the power consumption of the electrical resistance element 11 from the start of the increase in the energization (power consumption amount) to the electrical resistance element 11 until the target power consumption G (requested value of the surplus power consumption request) is reached is increased.

[0058] On the other hand, when a new first power consumption request (air-conditioning power consumption request) is received (when increasing (starting) the supply of power (power consumption) to the electrical resistance element 11) while the electrical resistance element 11 is not energized (a "no power consumption request" state), the slow start processing unit 172 controls the average rate of increase in power consumption of the electrical resistance element 11 from the start of the increase in power supply (power consumption) to the electrical resistance element 11 (start of PWM control) until the target power consumption G (request value of the air-conditioning power consumption request) is reached and the increase in the duty ratio ends, so that the rate is smaller than that of the fast start processing unit 171. Note that in the slow start processing unit 172, the average rate of increase in power consumption of the electrical resistance element 11 from the start of the increase in power consumption until the target power consumption G is reached is equivalent to, for example, the average rate of increase in power consumption of the electrical resistance element 11 from the start of the increase in power consumption until the target power consumption G is reached in a conventionally known heating device when power is consumed for air conditioning purposes.

[0059] In this embodiment, the "average increase rate of the duty ratio" is "the average value of the increase rate of the duty ratio during the period from the time when the increase in power consumption starts (the start of PWM control) until the target duty ratio Dm corresponding to the set target power consumption G is reached and the increase in the duty ratio ends," and as an example, is set by the increase amount (increase amount) of the duty ratio per program processing cycle. Specifically, in the fast start process, assuming that the time from the start of PWM control until the target duty ratio Dm is reached is shorter than a predetermined time (e.g., 1 to 5 seconds), the increase in the duty ratio per processing period is set to 1.0% or more when the program processing period is 20.0 msec or less, preferably 1.0% or more when the program processing period is 10.0 msec or less, more preferably 1.0% or more when the program processing period is 5.0 msec or less, and even more preferably 1.0% or more when the program processing period is 1.0 msec or less. For example, assuming that the processing period may fluctuate, the increase in the duty ratio per processing period is set to 1.0% or more. In other words, the average duty ratio increase rate in the high-speed start process is, for example, 0.05% / msec or more, preferably 0.1% / msec or more, more preferably 0.2% / msec or more, and most preferably 1.0% / msec or more. The average duty ratio increase rate is appropriately selected so as to achieve these rates in accordance with the combination of the processing period and the increase amount of the duty ratio.

[0060] Based on the same concept, in the slow start process, for example, when the program processing period is 1.0 msec or longer, the increase in the duty ratio per processing period is preferably less than 1.0%, when the program processing period is 5.0 msec or longer, the increase in the duty ratio per processing period is preferably less than 1.0%, when the program processing period is 10.0 msec or longer, the increase in the duty ratio per processing period is desirably less than 1.0%, and more preferably when the program processing period is 20.0 msec or longer. For example, taking into account the possibility that the program processing period may fluctuate, the increase in the duty ratio per program processing period is set to 0.2% or less. In other words, the average duty ratio increase rate in the slow start process is lower than the average duty ratio increase rate in the fast start process, and is preferably, for example, lower than 0.2% / msec or lower than 0.1% / msec, more preferably lower than 0.05% / msec, and even more preferably 0.02% / msec or lower.

[0061] In the case of high-speed start processing, the increase in duty ratio per program processing cycle may be changed to 1.0% or more, 5% or more, 10% or more, etc. (the same applies to low-speed start processing).

[0062] The target power consumption G is, for example, 200 W to 10 kW. The target duty ratio Dm varies depending on the power consumption request received each time, but the maximum value of the duty ratio assumed for the heating device 10 (hereinafter referred to as the "maximum duty ratio") is the duty ratio when the target power consumption G (requested value) is at its maximum (for example, 10 kW).

[0063] In this way, in this embodiment, when surplus power is generated, it can be consumed efficiently and reliably because it is consumed by heat generation in the electrical resistance element 11. In addition, when surplus power is generated, the slope of the output power to the electrical resistance element 11 is made to rise sharply, so that the surplus power can be consumed early.

[0064] On the other hand, for example, when electricity is consumed for air conditioning, the slope of the output power to the electrical resistance element 11 is made gentler than in the case of surplus power consumption (conventional control), thereby preventing the heating device 10 from being subjected to an excessive load due to the power consumption.

[0065] After the target power consumption G is reached, the voltage applied to the electric resistance element 11 is PWM-controlled based on the power consumption requests that are subsequently received, thereby controlling the power supply to the electric resistance element 11. In this way, the electric resistance element 11 consumes the power required by heat generation.

[0066] While the control means 13 is consuming power based on a certain power consumption request (e.g., a first power consumption request), the control means 13 may receive a power consumption request containing a request value greater than the requested value. In this case, the control means 13 increases the output power based on the most recent (maximum at that time) request value. This is the case where the control means 13 increases the current supply to the electrical resistance element 11. That is, the control means 13 determines whether the fast start processing unit 171 or the slow start processing unit 172 should be used for control based on the most recent received power consumption request using the start processing determination means 16, and controls the opening and closing of the upper layer IGBT 121 and the lower layer IGBT using either processing unit. In this case, for example, if the most recent power consumption request is the second power consumption request, the control is performed by the fast start processing unit 171, and the difference between the current power consumption and the new target power consumption G based on the most recent request value is achieved in a short time (i.e., the output power is increased sharply).

[0067] That is, when the control means 13 receives a second power consumption request including a second request value (latest request value) that is greater than a certain (earlier) power consumption request (earlier request value) among a plurality of power consumption requests while performing switching control of the upper layer IGBT 121 and the lower layer IGBT 122 based on the certain (earlier) power consumption request (earlier request value), the control means 13 starts control by the high-speed start processing unit 171 using the latest request value (second request value) as the new target power consumption G.

[0068] Furthermore, when the control means 13 receives a first power consumption request including a first request value (latest request value) that is greater than a certain (earlier) power consumption request (earlier request value) among a plurality of power consumption requests while performing opening and closing control of the upper layer IGBT 121 and the lower layer IGBT 122 based on the certain (earlier) power consumption request (earlier request value), the control means 13 starts control by the slow start processing unit 172 with the latest request value (first request value) as the target power consumption G.

[0069] A more detailed explanation will be given again with reference to Fig. 4. Fig. 4(I) and Fig. 4(J) are diagrams showing an example of the change over time in output (power) of the electrical resistance element 11 when the target power consumption G increases (increase 2) during a period when output based on a certain power consumption request (output increase 1) is being performed.

[0070] FIG. 4(I) shows an example in which a second power consumption request is received that includes a second request value (the most recent request value (target power consumption G2)) that is greater than the first request value during a period in which slow start processing is executed based on a first power consumption request and output is being performed based on the first request value (the previous request value (target power consumption G1)) from the start time SS (when power consumption starts to increase). In this case, the control means 13 executes fast start processing and performs output based on the second request value (target power consumption G2) from the start time FS (when power consumption starts to increase). The increase in the request value at the start time FS of the fast start processing is the difference ΔG between the second request value (target power consumption G2) and the previous first request value (target power consumption G1).

[0071] FIG. 4(J) shows an example in which a first power consumption request is received that includes a first request value (the most recent request value (target power consumption G1)) that is greater than the second request value during a period in which a fast start process is executed based on a second power consumption request and output is being performed based on the second request value (the previous request value (target power consumption G2)) from the start time FS (when power consumption starts to increase). In this case, the control means 13 executes a slow start process and performs output based on the first request value (target power consumption G1) from the start time SS (when power consumption starts to increase). The increase in the request value at the start time SS of the slow start process is the difference ΔG between the first request value (target power consumption G1) and the previous second request value (target power consumption G2).

[0072] FIGS. 4(I) and 4(J) are merely examples, and the power consumption requirement in the first increase (increase 1) may be the first power consumption requirement or the second power consumption requirement.

[0073] The above describes an example in which the voltage control in the power control means 17 is PWM control, but this is not limiting and the voltage may be controlled by, for example, a PFM (Pulse Frequency Modulation) method in which the on (or off) time of a pulse is kept constant and the off time (or on time) is varied.

[0074] <<Pre-charging method>> 3 again, the pre-charge means 18 realizes the pre-charge function and closes (turns off) the upper layer IGBT 121 and opens (turns on) the lower layer IGBT 122 to accumulate charge in the bootstrap capacitor 125 when the forcing shutoff means 20 determines that the forcing shutoff condition is met or when the request determination means 15 determines that "none of the multiple power consumption requests exists." "None of the multiple power consumption requests exists" refers to the case where the request acquisition means 14 acquires power consumption requests at a predetermined cycle but the request value is "0" (less than the minimum request value and considered to be "0"). In this case, the on-times of the upper layer IGBT 121 and the lower layer IGBT 122 do not overlap, and the electrical resistance element 11 is not energized.

[0075] The pre-charging means 18 controls the upper layer IGBT 121 to be continuously turned off and the lower layer IGBT 122 to be continuously turned on during a period when no current is passed through the electrical resistance element 11, and accumulates (pre-charges) a sufficient charge in the bootstrap capacitor 125 at the start of control when "power consumption request is present" occurs thereafter. This "sufficient charge at the start of control" refers to a charge that can generate a gate voltage that enables the upper layer IGBT 121 to be reliably turned on (driven in a substantially saturated region, i.e., fully on) during a period in which the target duty ratio Dm can be achieved. More specifically, it refers to the amount of charge (hereinafter referred to as "full-on possible charge amount") that can generate a gate voltage that enables the upper layer IGBT 121 to be fully on from the beginning (first pulse) at the maximum duty ratio (e.g., 94%) immediately after the start of PWM control.

[0076] Further explanation will be given with reference to Fig. 5. This figure is a schematic diagram comparing the presence and absence of pre-charging by the pre-charging means 18, and is a timing chart showing the states of the upper layer IGBT 121, the lower layer IGBT 122, and the bootstrap capacitor 125 around the timing when the fast start processing unit 171 starts control to cause a steep rise in heat generation (power consumption) in the electrical resistance element 11. Fig. 5(A) is an example of the case where pre-charging is performed by the pre-charging means 18 of this embodiment, and Fig. 5(B) is a comparative example showing the case where pre-charging is not performed.

[0077] 5(A) shows, from the top, the input signal to the upper layer IGBT 121 (pulse waveform voltage output by the upper layer driver 123), the gate voltage of the upper layer IGBT 121, the threshold voltage of the upper layer IGBT 121, the on (H) / off (L) state of the upper layer IGBT 121, the duty ratio, the input signal to the lower layer IGBT 122 (pulse waveform voltage output by the lower layer driver 124), and the on (H) / off (L) state of the lower layer IGBT 122. 5(B) shows, from the top, the input signal of the upper layer IGBT 121 (pulse waveform voltage output by the upper layer driver 123), the threshold voltage of the upper layer IGBT 121, the gate voltage of the upper layer IGBT 121, the on (H) / off (L) state of the upper layer IGBT 121, the duty ratio, the input signal of the lower layer IGBT 122 (pulse waveform voltage output by the lower layer driver 124), and the on (H) / off (L) state of the lower layer IGBT 122. In FIG. 5, the upper layer IGBT 121 is abbreviated as IGBT1, and the lower layer IGBT 122 is abbreviated as IGBT2.

[0078] The gate voltage of the upper layer IGBT 121 is generated by the bootstrap capacitor 125 and corresponds to the amount of charge stored in the bootstrap capacitor 125. The area (amount of overlap) of the duty ratio corresponds to the output of the electrical resistance element 11.

[0079] Referring to FIG. 5(A), when the pre-charging means 18 determines that "there is no power consumption request," during a period T1 (before timing t1) in which the electrical resistance element 11 is not energized, the pre-charging means 18 sets the input signal (IGBT2 input signal) of the lower layer IGBT 122 to "H" to turn the lower layer IGBT 122 on, and sets the input signal (IGBT1 input signal) of the upper layer IGBT 121 to "L" to turn the upper layer IGBT 121 off, thereby storing charge in the bootstrap capacitor 125.

[0080] The amount of charge stored in the bootstrap capacitor 125 is the full-on charge amount. The control means 13 (pre-charging means 18) maintains the upper layer IGBT 121 in an off state and the lower layer IGBT 122 in an on state until the full-on charge amount is accumulated. If a period continues after that when there is no power consumption request, the charge in the bootstrap capacitor 125 is discharged. Therefore, the control means 13 (pre-charging means 18) maintains the upper layer IGBT 121 in an off state and the lower layer IGBT 122 in an on state during a period when there is no power consumption request, so that at least the full-on charge amount can be maintained. As a result, when either "power consumption request is received," the upper layer IGBT 121 can be immediately turned on fully, enabling an early response to the power consumption request.

[0081] The bootstrap capacitor 125 is appropriately selected depending on the use of the product, with a capacity that can store the charge that can fully turn on the upper layer IGBT 121. This increases the degree of freedom in circuit design.

[0082] In this example, timing t1 is the timing when the PWM control start signal in control means 13 turns on ("H") and high-speed start processing by power control unit 17 starts. When the input signal (IGBT1 input signal) to upper layer IGBT 121 turns "H" at timing t1, a gate voltage (a voltage generated by the fully on-capable charge amount accumulated in bootstrap capacitor 125) exceeding the threshold voltage is applied to the gate of upper layer IGBT 121. This turns upper layer IGBT 121 on, and electrical resistance element 11 is energized during a period overlapping with the on-state of lower layer IGBT 122. Note that while FIG. 1A illustrates an example where output is at target duty ratio Dm from the first pulse, in reality, the duty ratio is slightly smaller than target duty ratio Dm initially (for example, at the first pulse). As upper layer IGBT 121 continues to be on, the charge in bootstrap capacitor 125 is consumed and the gate voltage gradually decreases.

[0083] When the input signal to the lower layer IGBT 122 becomes "L" at timing t2, the upper layer IGBT 121 turns on, the lower layer IGBT 122 turns off, and the conduction of the electric resistance element 11 stops.

[0084] When the input signal (IGBT2 input signal) of the lower layer IGBT 122 becomes "H" at timing t3, the lower layer IGBT 122 enters an ON state, and the electrical resistance element 11 is energized during a period overlapping with the ON state of the upper layer IGBT 121. Since a sufficient charge has been accumulated in the bootstrap capacitor 125, the gate voltage of the upper layer IGBT 121 gradually decreases, but does not fall below the threshold voltage during the period when the IGBT1 input signal is "H", and the upper layer IGBT 121 continues to be ON.

[0085] When the IGBT1 input signal goes low at timing t4, the upper layer IGBT 121 turns off, and the lower layer IGBT 122 continues to be on, causing charge to accumulate in the bootstrap capacitor 125.

[0086] When the input signal (IGBT1 input signal) to the upper layer IGBT 121 goes "H" at timing t5, the upper layer IGBT 121 turns on, and the electrical resistance element 11 is energized during the period overlapping with the on state of the lower layer IGBT 122.

[0087] When the input signal to the lower layer IGBT 122 goes "L" at timing t6, the upper layer IGBT 121 turns on, the lower layer IGBT 122 turns off, and the conduction of the electrical resistance element 11 stops. When the input signal to the IGBT2 goes "H" at timing t7, the lower layer IGBT 122 turns on, and the electrical resistance element 11 becomes conductive. Thereafter, this control is repeated during the period when "power consumption request exists."

[0088] 5B is a comparative example in which pre-charging is not performed. In this case, during a period T1 in which there is no power consumption request and the electrical resistance element 11 is not energized, the bootstrap voltage 125 is in a (completely) discharged state, and a gate voltage exceeding the threshold voltage of the upper layer IGBT 121 cannot be generated.

[0089] In this state, even if the IGBT1 input signal becomes "H" at timing t8, a gate voltage exceeding the threshold voltage cannot be applied to the gate of the upper layer IGBT 121, and the upper layer IGBT 121 remains off.

[0090] When the IGBT2 input signal goes high at timing t9, the lower layer IGBT 122 is turned on. At this timing, the upper layer IGBT 121 remains off, and the electrical resistance element 11 is not energized.

[0091] At this time, the upper layer IGBT 121 is off and the lower layer IGBT 122 is on, so charge is stored in the bootstrap capacitor 125, but the IGBT1 input signal is "H" at this timing. In other words, although the upper layer IGBT 121 receives an on input signal, it cannot be turned on due to a lack of charge, and even if an amount of charge sufficient to generate the threshold voltage of the upper layer IGBT 121 were to be stored, it would be immediately consumed by turning on the upper layer IGBT 121. In other words, the upper layer IGBT 121 turns on momentarily and then off, and a state in which charge is difficult to store in the bootstrap capacitor 125 continues.

[0092] At timing t10, when the IGBT1 signal goes "L", the upper layer IGBT 121 turns truly off and the lower layer IGBT 122 turns on, so that charge starts to accumulate in the bootstrap capacitor 125. By repeating this operation, the charge accumulated in the bootstrap capacitor 125 increases at a gradual rate, and after a predetermined time has passed, it becomes possible to accumulate enough charge to turn on the upper layer IGBT 121.

[0093] For example, even if a gate voltage exceeding the threshold value can be generated at timing t11, the on-time of the upper layer IGBT 121 will not continue while the amount of charge stored in the bootstrap capacitor 125 is small, and the electrical resistance element 11 will not be sufficiently energized (the actual duty ratio will not reach the target duty ratio Dm).

[0094] In this way, in a configuration that does not perform pre-charging, even if a high-speed start process is performed as a command, it takes time for the electrical resistance element 11 to be able to generate sufficient heat, resulting in a delay from the start of the process (timing t8).

[0095] In this embodiment, while waiting for the acceptance of a power consumption request, the bootstrap capacitor 125 can be sufficiently charged. Specifically, the pre-charging means 18 stores a charge sufficient to fully turn on the upper layer IGBT 121 from the first pulse immediately after the power control means 17 starts processing (immediately after the PWM control start signal turns on ("H")).

[0096] In this example, the case where power is received first before the fast start process has been described, but the pre-charging means 18 also performs pre-charging before the slow start process. In other words, whether the control is performed by the fast start processing unit 171 or the slow start processing unit 172, the bootstrap capacitor 125 is sufficiently charged while waiting for the acceptance of a power consumption request. This allows the control means 13 to immediately (instantly) start the fast start process or the slow start process when it determines that "a power consumption request has been made."

[0097] <Heater control processing> An example of the electric resistance element 11 (heater) control process executed by the control means 13 of the heating device 10 will be described with reference to Fig. 6. Fig. 6 is a flow diagram showing the flow of the heater control process. The heating device 10 repeatedly executes the heater control process shown in Fig. 6 during its operation. That is, in this example, the cycle from step S01 to step S17 (or, for example, the cycle from execution of step S15 to execution of the next step S15) can be said to be the above-mentioned program cycle process.

[0098] First, in step S01, for example, the forcing shutoff means 20 determines whether or not an abnormality has been detected (whether or not the forcing shutoff conditions are met). Specifically, for example, it determines (1) whether or not a protection / failure sensor has been detected, and (2) whether or not overvoltage sensor failure detection has not been completed. If a protection / failure sensor has been detected (Yes), the forcing shutoff means 20 proceeds to step S19. Also, if overvoltage sensor failure detection has not been completed (Yes), the forcing shutoff means 20 proceeds to step S19. On the other hand, if a protection / failure sensor has not been detected and overvoltage sensor failure detection has been completed (No), the forcing shutoff means 20 proceeds to step S03.

[0099] In step S03, the request acquisition means 14 synchronously (almost simultaneously) acquires a first power consumption request from the air conditioning ECU 1 and a second power consumption request from the charging ECU 2 through periodic interrupt processing. The first power consumption request and the second power consumption request each include a request value. The request value is a value (information) corresponding to the target power consumption G, and even if there is no actual power consumption request, the request value includes information indicating that there is no consumption request (for example, "0" or a value less than the minimum request threshold). In other words, in one interrupt processing, the request acquisition means 14 acquires at least the first power consumption request and the second power consumption request as a pair, but may also acquire other requests (commands) in addition to these.

[0100] Note that steps S01 and S03 may be performed almost simultaneously, or the order of steps S01 and S03 may be reversed.

[0101] In step S05, the request determination means 15 determines whether the first power consumption request and the second power consumption request have been acquired normally, and whether there is a substantial power consumption request based on these.

[0102] The request determination means 15 compares each of the first request value and the second request value with a preset minimum request threshold (e.g., 200 W), and if both the first request value and the second request value are less than the minimum request threshold, it determines that there is no power consumption request, and regards the request value as 0, for example.If the request value is equal to or greater than the minimum request threshold, it determines that there is an actual power consumption request from the air conditioning ECU 1 or the charging ECU 2.

[0103] If it is determined in step S05 that "there is a power consumption request", the process proceeds to step S07, and if it is determined that "there is no power consumption request", the process proceeds to step S19.

[0104] In step S07, for example, the request determination means 15 compares the first request value included in the first power consumption request with the second request value included in the second power consumption request, determines the larger value as the actual request value, and sets the actual request value as the target power consumption G as a parameter for PWM control.

[0105] In step S09, the start processing determination means 16 determines whether the acquired power consumption request should be processed by the high-speed start processing unit 171 or the low-speed start processing unit 172, based on a predetermined determination condition.

[0106] Here, as an example, if the power consumption request received by the request determination means 15 is the second power consumption request (surplus power consumption request) (Yes), it is determined that processing will be performed by the fast start processing unit 171, and the process proceeds to step S11. On the other hand, if the power consumption request received by the request determination means 15 is the first power consumption request (air conditioning power consumption request) (No), it is determined that processing will be performed by the slow start processing unit 172, and the process proceeds to step S13.

[0107] In step S11, control is performed by the fast start processing unit 171. The fast start processing unit 171 sets PWM control parameters for fast start processing. One of the PWM control parameters is a parameter that controls the opening and closing of the upper layer IGBT 121 and the lower layer IGBT so that the target power consumption G is reached in a short time when the current supply to the electrical resistance element 11 is increased (for example, increased from "0"). Specifically, the upper limit of the increase amount (increase amount) of the duty ratio per program processing cycle is, for example, 15% to 25%, preferably 20%. This increase amount is larger than the increase amount of the duty ratio in the slow start processing unit 172.

[0108] Based on this increase amount, the fast start processing unit 171 sets PWM control parameters to increase the duty ratio. As a result, in the next step S15, a PWM control execution step, the duty ratio increases by the set increase amount (for example, 15%) for each predetermined period (one period), for example, and the target power consumption G is reached in a shorter time than in the control by the slow start processing unit 172.

[0109] In step S13, control is performed by the slow start processing unit 172. The slow start processing unit 172 sets PWM control parameters for the slow start processing. One of the PWM control parameters is a parameter that controls the opening and closing of the upper layer IGBT 121 and the lower layer IGBT so that when the current supply to the electrical resistance element 11 is increased (for example, increased from "0"), the target power consumption G is reached in a longer time than under the control of the fast start processing unit 171. Specifically, the upper limit of the increase (increase) in the duty ratio per program processing cycle is, for example, 0.12% to 0.18%, preferably 0.15%.

[0110] Based on this increase amount, the slow start processing unit 172 sets PWM control parameters to increase the duty ratio. As a result, in the next step S15, a PWM control execution step, the duty ratio increases by the set increase amount (e.g., 0.2%) for each predetermined period (one period), for example, and the target power consumption G is reached in a longer time than in the control by the fast start processing unit 171.

[0111] In step S15, the power control means 17 (high speed start processing unit 171 or low speed start processing unit 172) starts PWM control of the voltage applied to the electrical resistance element 11 based on the set PWM control parameters when the PWM control start signal is turned on ("H"), thereby controlling the supply of electricity to the electrical resistance element 11. In this way, the electrical resistance element 11 consumes the power required by heat generation (target power consumption G).

[0112] In step S17, various sensor values ​​(for example, the actual power consumption (output) of the current electric resistance element 11, etc.) are updated, and the process returns to step S01.

[0113] Step S19 is a process performed when there is no power consumption request for the electric resistance element 11, that is, when the electric resistance element 11 is not conducting electricity. In step S19, the pre-charging means 18 turns the upper layer IGBT 121 off and the lower layer IGBT 122 on, and accumulates a full-on charge amount in the bootstrap capacitor 125.

[0114] <Modification of heater control process> In the determination of the high-speed start processing (step S09) shown in FIG. 6, an example has been described in which it is determined that in the case of the second power consumption request (surplus power consumption request), control is performed by the high-speed start processing unit 171 (step S11), and in the case of the first power consumption request (air conditioning power consumption request), control is performed by the low-speed start processing unit 172 (step S13).

[0115] However, the present invention is not limited to this, and control by the fast start processing unit 171 and control by the slow start processing unit 172 may be allocated based on a predetermined start processing determination flag. For example, a "fast flag" indicating that fast start processing is to be executed may be set in the first power consumption request (air conditioning power consumption request). Then, in determining whether to perform fast start processing (step S09), even for the first power consumption request (air conditioning power consumption request), if the fast flag is enabled (on, set, "1", etc.), it may be determined that control by the fast start processing unit 171 (step S11) is to be performed, and if the fast flag is disabled (off, not set, "0", etc.), it may be determined that control by the slow start processing unit 172 (step S13) is to be performed. Furthermore, the high-speed flag may also be set in the second power consumption request (surplus power consumption request), and step S11 and step S13 may be allocated based on the high-speed flag.

[0116] With this configuration, when it is desired to heat the air inside the vehicle quickly, for example, when the outside air temperature is low, the slope of the output power can be increased steeply, thereby speeding up the temperature rise inside the vehicle.

[0117] Also in this case, by making it possible to select between control by the high-speed start processing unit 171 and control by the low-speed start processing unit 172 (not only control by the high-speed start processing unit 171), it is possible to prevent an excessive load from being applied to the heating device 10.

[0118] Furthermore, in setting the PWM control parameters in step S11 and / or step S13, the increase amount of the duty ratio may be determined each time by combining the power consumption request (request value) with the actual power consumption (sensor value) of the electrical resistance element 11.

[0119] FIG. 7 is an example of a timing chart showing command signals included in a power consumption request with the maximum requested value received by the request determination means 15 and changes in the state of the heating device 10 based on these command signals.

[0120] In this example, the power consumption request includes a "high-speed flag," which indicates that control by the high-speed start processing unit 171 (control in which the output rises sharply) is executed when the flag is "1," and control by the low-speed start processing unit 172 (control in which the output rises at a gentle slope) is executed when the flag is "0." The "high-speed flag" and "request value" in the figure indicate changes in the command signal included in the power consumption request, and the "PWM control start signal" and "heater power consumption" indicate changes in control (determination) or changes in output in the heating device 10.

[0121] First, at timing t12, the forced shutoff condition is not satisfied and the request acquisition means 14 acquires the first set of power consumption requests (the first power consumption request or the second power consumption request) (step S03 shown in FIG. 6). The power consumption request (command signal) with the larger requested value includes the upper limit of the requested power (e.g., 10 kW) as the requested value and "1" as the high-speed flag. This causes the request determination means 15 to determine that "a power consumption request exists." The target power consumption G is then set to 10 kW, and the high-speed flag is set to "1" (enabled) (steps S05 and S07).

[0122] Timing t13 is the timing when the control in the fast start processing unit 171 is determined through the determination by the start processing determination means 16 (step S11), and the target power consumption G is set to 10 kW (target duty ratio Dm is, for example, 94%, and the increase amount of the duty ratio per unit period is, for example, 20%), and PWM control in the fast start processing unit 171 (step S15) is started. Timing t13 starts, for example, 4 msec at most after timing t12. In other words, the time from obtaining the power consumption request (step S03) to executing PWM control (step S15) in the flow shown in FIG. 6 is, for example, 4 msec at most.

[0123] Thereafter, the target power consumption G is reached at timing t14 through control by the power control means 17 (fast start processing unit 171). That is, at this timing, the electrical resistance element 11 is generating heat at 10 kW. The time from the start of control by the fast start processing unit 171 (timing t13) until the target power consumption G (timing t14) is reached is, for example, approximately 200 msec.

[0124] Thereafter, until timing t15, the power consumption request is repeatedly accepted with the same command (request value 10 kW and high-speed flag "1"). The electric resistance element 11 continues to generate heat at 10 kW under the control of the power control means 17. The high-speed flag is determined when the request value (target power consumption G) increases. In other words, even if it is included in the power consumption request, if the target power consumption G does not increase (if the target duty ratio Dm is reached), there is no effect on the control.

[0125] Timing t15 is the timing at which the request determination means 15 determines that there is no power consumption request. This is the case, for example, when the request values ​​of a set of power consumption requests acquired by the request acquisition means 14 are all "0 (less than the minimum request threshold)." At timing t15, the request values ​​become "0," and the power consumption of the electrical resistance element 11 also becomes 0 W.

[0126] Timing t16 is the timing when the request acquisition means 14 acquires a power consumption request (the first power consumption request or the second power consumption request) (step S03 shown in FIG. 6). The power consumption request (command signal) with the larger requested value includes a requested value of 10 kW and a high-speed flag of “0.”

[0127] The request determination means 15 determines that there is a power consumption request, sets the target power consumption G to 10 kW, and accepts the high-speed flag as "0" (invalid) (steps S05, S07).

[0128] Timing t17 is the timing when the control by the slow start processing unit 172 is determined through the determination by the start processing determination means 16 (step S13), and the target power consumption G is set to 10 kW (target duty ratio Dm is, for example, 94%, and the increase amount of the duty ratio per unit period is, for example, 0.2%), and PWM control (step S15) by the slow start processing unit 172 starts. Timing t17 also starts, for example, 4 msec at most after timing t16.

[0129] Thereafter, the target power consumption G is reached at timing t18 through control by the power control means 17 (slow start processing unit 172). In other words, at this timing, the electrical resistance element 11 is generating heat at 10 kW. The time from the start of control by the slow start processing unit 172 (timing t16) until the target power consumption G (timing t18) is reached is, for example, approximately 6 seconds. At timing t19, the required value becomes "0" again, and the power consumption of the electrical resistance element 11 also becomes 0 W.

[0130] An example of the heating device 10 of this embodiment has been described above, but the request acquisition means 14, request determination means 15, start processing determination means 16, power control means 17, and pre-charging means 18 described in Fig. 3 are just examples, and any configuration may be used as long as it is capable of realizing at least the request acquisition function, request determination function, start processing determination function, power control function, and pre-charging function of the heating device 10 described above. For example, multiple of these means (e.g., the request acquisition means 14 and the request determination means 15, or the start processing determination means 16 and the power control means 17) may be configured as a single means, or a single means (e.g., the start processing determination means 16, the power control means 17, etc.) may be configured to be divided into multiple means.

[0131] Furthermore, some or all of these hardware means may be configured as software, or vice versa. Furthermore, these means are not limited to being realized by electronic components on one control board 1, but may be configured by electronic components provided on multiple control boards.

[0132] In the above embodiment, the sender of the first power consumption request (first request sending means) and the sender of the second power consumption request (second request sending means) are the air conditioning ECU 1 and the charging ECU 2, which are external devices of the heating device 10. However, the sender of the first power consumption request (first request sending means) and / or the sender of the second power consumption request (second request sending means) may be means included in the heating device 10.

[0133] For example, the heating device 10 may be configured to acquire information from a vehicle air conditioning device, which is an external device, and generate a first power consumption request in a first request transmission means within the heating device 10, which then transmits the first power consumption request to the request acquisition means 14 of the heating device 10. Similarly, the heating device 10 may be configured to acquire information from a vehicle control unit, which is an external device, and generate a second power consumption request in a second request transmission means within the heating device 10, which then transmits the second power consumption request to the request acquisition means 14 of the heating device 10.

[0134] Furthermore, the sender of the first power consumption request is not limited to the control unit of the vehicle air conditioning device (air conditioning ECU1) but may be the control unit (ECU) of another device, and the sender of the second power consumption request is not limited to the vehicle control unit (charging ECU2) but may be the control unit (ECU) of another device.

[0135] Furthermore, the upper layer switching element 121 and the lower layer switching element 122 are not limited to IGBTs, and may be other voltage-driven transistors. For example, they may be field-effect transistors, and more specifically, they may be enhancement-type n-channel insulated gate field-effect transistors (e.g., MOSFETs: metal-oxide-semiconductor field-effect transistors).

[0136] Furthermore, the voltage control in the power control means 17 may be set by appropriately selecting both PWM control and PFM control, for example, when starting to use the heating device 10, or may be set so that both can be switched (selected each time) during operation of the heating device 10. Other types of voltage control may also be used.

[0137] The heating device of the present invention is not limited to the above-described embodiment, and it goes without saying that various modifications can be made without departing from the spirit of the present invention. [Industrial Applicability]

[0138] The heating device 10 of the present invention can be used in the field of vehicle accessories. [Explanation of symbols]

[0139] 1 Control board 2 cases 3 Pipe 4 Regenerative device 5 Power supply section 6. Energy storage device 10 Heating device 11 Electrical resistance element 12 Driving means (heater driving means) 13 Control means (control unit) 14 Request acquisition means 15 Request determination means 16 Start processing determination means 17 Power Control Means 18 Ahead charging means 19. Means of communication 121 Upper layer switching element 122 Lower layer switching element 123 Upper Driver 124 Lower Driver 125 Upper Capacitor (Bootstrap Capacitor) 126 Lower Capacitor 130 Driver power supply 171 High-speed start processing unit 172 Slow start processing unit Dm Target duty ratio G Target power consumption

Claims

1. an electric resistance element capable of generating heat in response to a plurality of power consumption requests from the vehicle; an upper layer switching element and a lower layer switching element connected in series via the electrical resistance element; a bootstrap capacitor for storing charge for turning the upper layer switching element into an open state; a control means for controlling the opening and closing of the upper layer switching element and the lower layer switching element to perform conduction / cutoff control of the electrical resistance element, At least one of the plurality of power consumption requests is a request transmitted based on control of a regenerative device and / or a power storage device of the vehicle, and is a power consumption request (hereinafter referred to as an "excess power consumption request") for consuming surplus power when regenerative power generated by the regenerative device during braking exceeds the amount of power stored in the power storage device, the control means has a high-speed start processing unit that controls the opening and closing of the upper layer switching elements and the lower layer switching elements so that an average increase rate of power consumption of the electric resistance elements increases when the current supply to the electric resistance elements is increased, The control means When it is determined that none of the plurality of power consumption requests exists, the upper layer switching element is closed and the lower layer switching element is opened to store the charge in the bootstrap capacitor; When it is determined that there is a request to consume the surplus power, the electrical resistance element is energized to generate heat; When at least the surplus power consumption request is received, control is performed by the high-speed start processing unit, The control means By sufficiently charging the bootstrap capacitor while waiting for the acceptance of the power consumption request, the control means starts control by the fast start processing unit immediately when it determines that the power consumption request has been made. A heating device characterized by:

2. One of the plurality of power consumption requests is a power consumption request for heating air in an air conditioning device of the vehicle (hereinafter referred to as an "air conditioning power consumption request"), which is transmitted based on control of the air conditioning device.

2. The heating device according to claim 1.

3. The control means a slow start processing unit that controls the opening and closing of the upper layer switching elements and the lower layer switching elements so that the average increase rate of the power consumption is smaller than that of the fast start processing unit when the current supply to the electric resistance elements is increased; 3. The heating device according to claim 1 or 2.

4. The control means When the air conditioning power consumption request is received, control is performed by the slow start processing unit.

4. A heating device according to claim 3, which is dependent on claim 2.

5. a request acquisition means for synchronously acquiring the plurality of power consumption requests; the control means causes the electric resistance element to generate heat based on a maximum requested value among the requested values ​​included in the plurality of power consumption requests. The heating device according to any one of claims 1 to 4.

6. When the control means receives the surplus power consumption request including a request value larger than the request value included in the power consumption request during a period in which the control means is executing the switching control based on the power consumption request, the control means starts control by the fast start processing unit using the larger request value as a new target power consumption. The heating device according to any one of claims 1 to 5.

7. When the control means receives an air conditioning power consumption request that includes a request value greater than the request value included in the power consumption request during a period in which the control means is executing the opening and closing control based on a certain power consumption request, the control means starts control by the slow start processing unit using the greater request value as a new target power consumption.

5. The heating device according to claim 4.

8. the air conditioning power consumption request includes a start processing determination flag, and if the start processing determination flag indicates a high-speed start, the control means executes control by the high-speed start processing unit.

3. The heating device according to claim 2.

9. the control means is configured to PWM-control the conduction of the electrical resistance element, the high-speed start processing unit executes control to reach a target duty ratio corresponding to the power consumption request in a short time, the slow start processing unit executes control to reach a target duty ratio corresponding to the power consumption request in a longer time than the fast start processing unit; 4. The heating device according to claim 3.

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